Molding machine clamp



Dec. 5, 1933. E. F. OYSTER 1,937,910

MOLDING MACHINE CLAMP Filed May 23, 1932 1 v 0 O O i W W INVENTOR.

6dr? .5? Oyafer ATTQRNEY Patented Dec. 5, 193?;

1,937,910 MOLDING MACHINE CLAMP Earl F. Oyster, Shaker, Heights, Ohio, assignor t The Osborn Manufacturing Company, Cleveland, Ohio, a corporationof Ohio Application May 23, 1932. Serial No. 612,916

6 Claims.

The aim of this invention is to provide a means whereby clamps on a rockover molding machine can be moved simultaneously by operation of either one of them into position to engage a flask 8 on, the rockover table and so hold it in place during the 'rockover operation, or moved out of the way of the flask. It is particularly adapted for use on open machine, that is, those in which the flask is held entirely from one side, so that flasks can be handled which are longer and wider than the immediate supporting means, and longer than the width between the rockover arms. The rockover machines and their clamps to which the invention is applied are old, but it has not hitherto been the practice to arrange for the simultaneous swinging of such clamps on accountpf the fact that the rockover elements of the mechanism leave only a very limited space for such cross connections, and therefore some of i the more .obvious types of connection, such as, for example, rod and lever, could not be used. On the other hand, the connections must be of a nature which are simple and strong, accessible for repair when necessary, and readily repaired. Nothing of the sort having been developed, the present practice is to have the operator of the machine pull out or swing in each clamp arm separately, stepping from one side of the machine to theother to do it. To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawing and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In the drawing Fig. l is a side elevation of the improved mechanism applied to a rockover machine, showing a flask in place thereon; and Fig. 2 is a corresponding plan view, omitting the flask.

The usual elements of the machine comprise a jolt table 1 adapted to be rocked over by a yoke 2 pivoted at 3 in standards 4 having the usual horizontal arms 5 for lifting the table and actuated by suitable mechanism, not shown. The yoke 2 includes the usual vertical side members i 6 to which the clamps are permanently secured. The clamps comprise brackets 7, normally horizontal, with shoes 8 on their respective outer ends to engage the top of the flask and hold the flask down upon the jolt table. The brackets 7 are 55: shown in both figures swung in' over the flask swinging either of the brackets 7 outward and ready for clamping, but up in the released position, clear of the flask, the shoes 8 being positioned over the flask 9. The clamps are actuated by air pressure to be applied to the cylinders 10 which are securedto the side members 6. The brackets include vertical elbows, enlarged at their, lower ends at 11 and there fastened both for reciprocation and rotation to pistonrods 12, the pistons of which, not shown, are in the cylinders 10. .Above the enlargements 11 the rods 12 pass through bearings in vertically spaced ears 13 and 15 on the side members 6. The upper ends of the rods 12 carry swingout sheaves l4 keyed to rotate with their respective shafts and held in place vertically between the ears 13 and 15. Bushings 16 on the upper ends of the clamp piston rods 12 exclude sand from the rod bearings. A crossed pulley 17 connects the sheaves 14 on the opposite sides of the machine, whereby inward swings the opposite one also outward or inward, as the case may be. Stops such as 18 and 19 on the members 11 limit the swing in and out of the brackets 7.

A brief summary of the operation follows. When the flask is placed on the table 1, the pistons in the cylinders 10 are in their uppermost position and the shoes 8 therefore clamp the top of the flask. The operator swings inward whichever of the brackets? is most convenient to him, which thus, by the crossed belt 17, swings the other arm also inward. Air now being applied to the cylinders 10, the clamps'are moved down, holding the flask firmly between the shoes 8 and the table 1. The sheaves 14 being keyed to the rod 12, are not moved up or down by the motion of the rod. After the flask has been rocked over in the usual way, bringing the table 1 on top and the clamps '7 underneath, the air pressure being released, the brackets '7 and the shoes fall clear of their flask, whereupon the operator swings out the most convenient one of the brackets 7, thereby swinging both out. It is to be noted that the arms 7 do not have to be swung to any definite position before they are clamped down. The position shown is a convenient one for a flask of the size and shape illustrated in the present drawing, but it will be appreciated that if the flask were smaller it might be desirable to swing the arms further in before applying the clamping pressure or if the flask were larger it might be desirable to have them further out before clamping.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means stated by. any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. In an open rockover machine, vertically movable clamps adapted to be swung in or out over a rockover table in the plane of the table and separately from any clamping movement, and cross connections for swinging said arms simultaneously.

2. In an open rockover machine, vertically movable clamps adapted to be swung in or out over a rockover table in the plane of the table and separately from any clamping movement, and pulley and belt cross connections for swinging said arms simultaneously.

3. In a rockover machine, a clamp, above a rockover table comprising arms pivoted above and at opposite sides of said table adapted to be swung over or out from said table in a plane parallel to the plane of the table, means for giving said arms limited movement toward and from the table, connecting means between said arms whereby swinging movement of one is imparted in the opposite direction to the other.

4. In a rockover machine, a clamp above a rockover table comprising arms pivoted above and at opposite sides of said table adapted to be swung over or out from said table in a planev parallel to the plane of the table, means for giving said arms limited movement toward and from the table, connecting means between said arms whereby swinging movement of one is imparted in the opposite direction to the other, said means comprising a pulley fast to each of said arms and a crossed belt connecting said pulleys.

5. In a rockover machine of the open type comprising a horizontal mold support, a pair of vertical air cylinders at one side of said support, piston rods extending from said cylinders, clamp arms fast to said rods, clamps on said arms parallel to said support, and connecting means between said rods for rotating both arms by an impulse applied to either, said connecting means occupying less extent in width than the diameter of the air cylinders.

6. In a rockover machine of the type having vertical side members carried near their tops by horizontal pivots, with horizontal mold-supporting arms extending from the bottoms of said side members, clamp means comprising a vertical air cylinder on each side member, a piston rod protruding from each said cylinder upwardly along the side member and movable axially and circumferentially, a clamp arm fast to each rod ineluding an upstanding offset portion and a horizontal portion extending from the upper end of said upstanding portion, a clamp on said horizontal portion parallel to the mold-supporting arms, a sheave of relatively small diameter fast upon each piston rod opposite the upstanding portion of the clamp arm, and a crossed flexible connector between said sheaves.

EARL F. OYSTER. 

